Do not get left in the dark!
Generac
Engine has overheated. Check airflow clearances, oil level, and air filter.
Need a technician? Skip the troubleshooting — open a service ticket and we'll handle it.
⚠ SAFETY FIRST: Disconnect battery (negative lead first) before inspecting internal components. Never work on a generator that may auto-start.
Overview
Engine has overheated. Check airflow clearances, oil level, and air filter.
Blocked airflow — generator installed too close to walls or in an enclosed space
Debris blocking cooling fins or air intake (leaves, dirt, insulation)
Ambient temperature too high (hot day + heavy load + poor ventilation)
Low oil level — oil also provides engine cooling
Dirty or clogged air filter
Faulty temperature sensor (false alarm)
Liquid-cooled: low coolant level or failed thermostat
Liquid-cooled: blocked radiator or failed cooling fan
Step-by-step workflow
Do not attempt to inspect or restart a hot engine. Allow at least 30 minutes of cooling time after a High Temperature shutdown before opening panels or touching engine components.
Air-cooled generators require adequate clearance on all sides for cooling airflow. Check that the installation meets Generac's minimum clearance requirements.
Engine oil provides a significant portion of cooling in air-cooled engines. Low oil can cause both a Low Oil Pressure alarm AND overheating.
A clogged air filter forces the engine to work harder, generating excess heat. This is especially common in dusty or high-pollen environments.
A faulty temperature sensor can trigger a High Temperature shutdown on a cool engine. If all physical checks are normal, sensor failure is likely.
After addressing the root cause and allowing the engine to cool fully, clear the alarm.
After reset
The code cleared and the unit returned to standby. Log the incident, confirm ready-to-run status, and monitor the next exercise cycle.
If the code returns immediately, stop resetting and move into service. The issue likely needs inspection of wiring, switches, or a controller-level component.
Prevention
Verify generator has 18-inch minimum clearances on all sides. Never install in an enclosed or semi-enclosed space.
Inspect and clear leaves, dirt, and debris from cooling fins and air intakes every season.
Check oil monthly. Low oil causes both pressure faults and overheating.
A&A Power Generators inspects cooling systems, oil, and temperature sensors at every visit. 888-991-4500
On very hot days, shed non-essential loads — ambient temperature plus load heat can push air-cooled units to their limit.
Receive High Temperature warnings instantly via the Generac Mobile Link app.
Let A&A Power Generators handle all preventative maintenance for your generator.
Still need help?
If the issue persists after following the workflow, route the unit into ticket, appointment, or consultation support so the team can take over with the right service path.
